Ivanov and Gustav are characters from the Blue Dragon anime.
HistoryEditIvanov and Gustav are twin Shadow Users from Gran Kingdom. They were the ones responsible for attacking the village Marumaro was at and capturing its inhabitants. They fought Marumaro, Zola, and Jiro outside the village, but retreated when they got their prisoners onboard.
They were visited by General Logi at the prison they ran. After General Logi defeated Zola, Jiro, and Marumaro, he left the rest to Ivanov and Gustav. Around this time, Shu managed to gain control of Blue Dragon and effortlessly defeated them in episode 5. Ivanov and Gustav made a cameo in a flashback where they attack Tonto's village for tribute to Nene.
ShadowsEditIvanov's shadow is a red armored, sword-wielding warrior that is good at offense. Gustav's shadow is a blue armored, shield-wielding warrior that's good at defense.
The two shadows can combine their attacks to form the Soul Matter attack.